Motor controller



Feb. 8; 19

" c. "r. EVANS MOTOR CONTROLLER original Filed June a, 1925 INVENTOR Menu/e3. 5W

A TTORNE Y Patented Feb. 8, 1927.

UNITED STATES PATENT OFFICE;

CLARENCE T. EVANS, OF WAUWA TOSA, WISCONSIN, ASSIGNOR TO THE CUTLER-HAM- HEB MFG. 00., O1 MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

'uoron CONTROLLER.

, Application filed .Tune 8, 1925, Serial No. 35,555. Renewed June 24, 1928.

y This invention relates to motor controllers and is particularl applicable to compensator starters for in uction motors. My co-pending application, Serial No. .5 741,104, filed October 2, 1924, discloses a manually operated compensator starter 1ncluding two movable contact elements, each having an extreme neutral position, all desired commutations of circult, including openin thereof, being effected by movement 0 the elements each from one extreme osition to another extreme position and reease thereof.

The present invention has among its ohla jects toprovide a-simple, eflicient and reliable automatic compensator starter having operating characteristics of the aforementioned starter. 'Another object is to provide an automatic com ensator starter of the aforesaid character having improved means associ ated therewith for timing interruption of starting connections and establishment of running connections.

Various other objects and advantages of the invention will hereinafter a pear. The accompanyin drawin sc ematically illustrates an embo iment o the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modification without departing from the spirit and scope of the appended claims.

Referring to the drawing, the same illustrates a compensator starter of the character disclosed in the aforementioned application, the same being adapted to control a three-phase alternating current motor M and including movable contact elements 1 and 2, and a set of stationary contacts 3. Contact elements 1 and 2 are normally in the extreme positions shown in the drawing and are movable downwardly from such positions into opposite extreme positions. Contact element 1 in its opposite extreme position cooperates with the set of stationary contacts 3 to establish starting connections and contact element 2 in its opposite extreme position cooperates with contact element 1 upon return of the latter to-its normal position to establish running connections. The running connections are interrupted by return of contact element 2 to normal position. Q

As set forth in the aforementioned application, contact elements 1 and 2 are provided with operating shafts 4 and 5 respectivelyand element 1 is provided with five contact members 6 to 10, inclusive, while element 2 is provided with three contact members 11, 12 and 13. The set of stationary contacts 3 includes .five contacts 14 to 18 inclusive each to cooperate with one of the contact members of element 1.

The aforedescribed switch mechanism is adapted to establish starting and running connections for a polyphase motor M from a three phase cirfcuit indicated by lines L L and L Lines L, L and L are permanently connected to contact members 6, 8 and 10 respectively of contact element 1 and the contact members 6 and 10 are permanently connected to contact members 11 and 13 respectively of contact element 2, the terminals M and M? of the motor M are permanently connected to contact members 7 and 9 respectively of contact element 1, while the intermediate terminal M of the motor is permanently connected to stationmy contact 16 and also to contact member 12 of element 2. Stationary contacts 14 and 18 are connected to one terminal of compensator windings C and C respectively, and

the opposite terminals of said windings are connected to terminal M of the motor. Also, the compensator windings C and C are provided with intermediate taps connected to stationary contacts 15 and 17 respectively.

The electrical connections made between the supply circuit and the motor when contact element 1 of the starter is moved into engagement with the set of stationary contacts 3 and out of engagement with the setof stationary contacts and into engagement with the contacts of element 2are apparent to those skilled in the art, and it is sulficient to state that in starting, the com ensator winding C is connected across p ase \LL while compensator winding C is connected across phase L L and b reason of the connection of terminals 1 and M of the motor to the intermediate taps of the compensator windings the motor will receive less than the full potential of the supply line. In the running position of the starter the terminals of the motor are directly connected to lines L, L and L through engagement of the contacts of element 1 with the contacts of element 2 and the motor will thus be supplied with full line potential.

. Contact element 1 is moved downwardly from its normal position into its opposite extreme position by an electromagnetic winding 19 while contact element 2 is moved downwardly from its normal position into its opposite extreme position by an electro magnetic winding 20. The energizing circuit of winding 19 is controlled through the medium of a normally open push button 21a normally closed push button 35 and two sets of auxiliary contacts, one including stationary contacts-22 and 22 and a normally open bridging. contact 22 and the other including stationary contacts 23 and 23 and a normally closed bridging contact 23. Contact 22 is operatively connected to shaft 4 through the medium of an arm 24 and a rod 25 while contact 23 is loosely mounted on the piston rod of a dash pot 27. The piston rod of dash pot 27 is connected to rod 25 by a spring26 and said piston rod is provided with a shoulder for opening contact 23 after a given upward movement of the dash pot piston.

Upon depression of push button 21, winding 19 is energized by a circuit extending from line L through push button 35 by conductor 28 through push button 21 conductors 29 and 30 through said winding, by conductor 31 through the normally closed auxiliary contact 23 and by conductor 32 to line L Immediately upon movement of contact element 1 into its starting position, auxiliary contact 22 closes to maintain winding 19 energized by a circuit extending from line L through push button by conductors 28 and 33 through auxiliary contact22 by conductors 34 and 30- through said winding by conductor 31 through contact 23 and by conductor 32 to line L After a predetermined interval determined by the setting of dash pot 27, switch 23 is opened to interrupt the aforedescribed maintaining circuit for winding 19 and the contact element 1 thenreturns to normal position.

Immediately upon movement of contact element 1 into its starting'position winding 20 is energized by a circuit extending from line L through a normally closed push button 35 through said winding and by conductor"36 to terminal M of the motor. As set forth in the aforementioned copending application the contacts of switch member 8 are arranged to momentarily bridge stationary contact 16 and contact member 12 during the change over from starting to running and it is thus apparent that the aforede scribed energizin circuit for winding 20 will be maintaine during such change over. Thus, contact element 2 is moved out of its normal position into its opposite extreme position immediately upon establishment of starting connections and remains in this position to establish running connections upon return of the contact element 1 to normal position, as above described.

From the foregoing it is apparent that starting connections are established immediately upon depression of push button 21 and after a predetermined interval determined by the setting -of dash pot 27 the starter acts automatically to interrupt the starting connections and establish running connections. The running connections are maintained by winding 20 subject to interruption under low voltage conditions in said winding or deenergization thereof by depression of push button 35.

What I claim as new and desire to secure by Letters Patent is:

1. In a motor controller, in combination, two contact elements each normally in a given extreme position and movable into an opposite extreme position, one of said elements in its opposite extreme position being adapted to establish starting connections, and the other being adapted in its opposite extreme position to cooperate with the former element in the normal position thereof to establish running connections, and an electromagnet associated with each of said elements for moving the same from its normal position into its opposite extreme position. 2. In a motor controller, in combination, two separately movable contact elements each normally in a given extreme position andmovable into an opposite extreme position, a plurality of stationary contacts to be engaged by one of said elements in its oppo- .site extreme position for establishment of starting. connections, said element being adapted upon return to the normal position to cooperate with the other of said elements in the opposite extreme position thereof to establish running connections, an electromagnet associated with each of said elements for moving the same from its normal position into its opposite extreme position,

and automatic means for deenergizing the electromagnet associated with said first mentioned element, after a predetermined interval upon movement of said first mentioned element into its opposite extreme position.

3. In a compensator starter for induction motors, in combination, apair of electromagnets, contacts controlled by one of said electromagnets to establish and interrupt starting connections, and contacts controlled by the other "of said electromagnets and adapted to cooperate with said former contacts to establish and integrupt running connections.

4. A compensator starter -for induction motors, comprising a movable contact element stationary tcontacts to be engaggd thereby for establishment of startin con nections, a second movable contact e ement to cooperate with the former contact element winding and for interrupting such circuitv for establishment of running connections, separate electromagnets for operating said elements, and control means associated with the electromagnet of said first mentioned element for timing interruption of starting connections and establishment of running" connections.

5. In a motor controller, in combination, two contact elements each normally in a given extreme position and movable. to an opposite extreme position, one of said elements in its opposite extreme position being adapted to establish starting connections and the other in its opposite extreme position, being adapted to co-operate with the former element in the normal position thereof to establish running connections, an electromagnetic operating winding associated with each of said elements for moving the same into its opposite extreme position, and control means for the winding associated with said first mentioned element including means for establishing an energizing circuit for said after a predetermined interval.

6. In a motor controller, in combination,

a' set of stationary contacts, a contact element normally in a given extreme position and movable into an o posite extreme position to engage said stationary contacts for establishment of starting connections, a second set of movable contacts normally in a given extreme position and movable into an opposite extreme position to be engaged by said 35 4 former element in the normal position thereof for establishment of running connections, an electromagnetic operating winding associated with said former element, means for establishing an energizing circuit for said winding and for interrupt ng the same after a predetermined period, and an electromagnetic operating winding associated with said latter element adapted to be energized upon establishment of starting connections and to be maintained energized during interruption of starting connections and establishment of running connections.

7. In a motor controller, in combination, two movable contact elements, each normally in a given extreme position and movable into anopposite extreme position, one of said contact elements being adapted in its op site extreme position to establish startmg connections, and the other being adapted in its opposite extreme position to cooperate with said former element in the normal po- 7 sition thereof to establish runningconnections', an electromagnetic winding for operating each of. said elements, aswitch for establishing an energizing circuit for the electromagnet associated with said former elemen't,a switch for maintaining said energizing circuit upon opening of saidformer switch, and means including a dash pot for openingsaid last mentioned switch after a tablish starting connections, a plurality of electromagnetic windings each for controlling certain of said movable contacts and control means for said windings insuring establishment of starting connections upon energization of one of said windings and establishment of running connections upon de energization of said former winding andenergization of the other of said windings.

9. A compensator starter for induction motors, comprising cooperating contacts, certain being movable and being engageable and disengageable to establish and interruptrunning connections and certain being stationary and being adapted to cooperate with certain of said movable contacts to establish starting connections, a plurality of electromagnetic windings each for controlling certain of said movable contacts, and control means for said windings insuring establishment of starting connections upon energization of one of said windings and establishment of running connections upon-deenergization of said former winding and error ization of the other of said windings, sai control means including means for deenergizing said first mentioned winding jafter a given interval upon establishment of starting connections. I

10. In a compensator starter for induction motors, in combination, a plurality of sets of contacts, certain of said sets being movable and certain being stationary, "and control means for said sets of contacts comprising a plurality of electromagnetic operating 1 windings providing for en'gagementof one of said sets of contacts by a sepond set of said contacts. for establishment of starting connections and forengagement of a third set of said contacts by said second set for establishment of running connections.

11. In a compensator starter for induction motors, in combination, a movable contact element biased towards a given sition and having an electromagnet assoclated there with for moving the same to another position, stationary contacts to be en aged bysaid element in said last mentione position to establish starting connections, contacts to be engaged by said element" upon return movement thereof out of said last ,men-- tioned position for establishment of running connectionsand control means for said lastmentioned contacts including a winding under the control of certain of said 'contacts.

12. A controlling. device for electric circuits comprising stationary contacts, movable contacts, and means including aplurality of electromagnetic windings for moving some of said movable contacts in one direction to engage certain of said stationary contacts to make one set of circuit connections, for moving some of the engaged movable contacts in another direction to disengage some of said engaged stationary contacts and to engage other movable contacts to make another set of circuit connections, and for disengaging all ofsaid con tacts.

In witness whereof, I have hereunto subscribed my name.

CLARENCE T.- EVANS. 

